Student Assessment $6$ Continued $...5.$ The Linear Variable Capacitor mounted on the DIGIAC $1750$ Trainer varies in

capacitance by changing: a the nature of the dielectric b varying the distance between the plates c varying the effective cross$-$sectional$-$area of the plates d the reactance of the capacitor due to a change in frequency

$6.$ From the information given in the notes about the main characteristics of the Linear Variable Capacitor, as the slug is moved the capacitance varies by about: a $25$pF$/$mm b $15$pF$/$mm c $1\mathrm{.}67$pF$/$mm d $0\mathrm{.}6$pF$/$mm

$7.$ When using a circuit similar to that investigated in Practical Exercise $6\mathrm{.}4,$ as the slug

of a Variable Capacitor is moved in towards the middle of the sleeve the output voltage: a remains the same b increases c changes polarity d reduces $8.$ The main disadvantage of using a single Strain Gauge in a Wheatstone Bridge

sensing circuit is that it: a has poor sensitivity b gives a non$-$linear response

c is affected by temperature d cannot be null$-$balanced

$9.$ The strain gauge bridge used in the DIGIAC $1750$ Trainer has: a one active and one dummy strain gauges b two active and two dummy strain gauges c four active strain gauges d two active and four dummy strain gauges $10.$ The difference between an active and a dummy strain gauge is that: a they are made of different materials b an active gauge is longer than a dummy

c an active gauge is shorter than a dummy d they are mounted in different directions